Internal-combustion engine.



H. G. CHATAIN.

INTERNAL COMBUSTION ENGINE.

APPLICATION FILED APR.23, 1912.

L1 12,263.. Patented Sept. 29, 1914.

Fig.2, Fig.1.

Witnesses: Inventor": Henri G. chataln may.

. To all ivhom. it may concern:

Be 1t known that 'I, Henri G. OHATAIN, a citizen of the United States, residing at type having HENRI e; 0341mm, OFYERIE, PENNSYLVANIA,

' company, A conrona ASSIGNOR TO GENERAL ELECTRIC TION OF'NEW YORK.

IN TERN AI -COMBUSTION ENGINE.

' Specification of Letters Patent.

Patented Sept. 29, 1914.

Application filed April 23, 1912. Serial No. 692,582.

Erie, county of Erie, State of Pennsylvania, have invented certain new and useful" Improvements in Internal-Combustion Engines, of which the following is a specification. The present invention relates to internal combustion engines of the constant pressure oppositely moving pistons in the same cylinder and operating on the twocycle plan, and has for its object to improve their construction and operation, particular reference being made to balancing the moving parts thereof and reducing the size of the apparatus as a whole.

' For a consideration of what I believe to be novel and my invention, attention is directed tothe accompanying description and claims appended thereto.

the accompanying drawing which illustrates one of the embodiments of ,my invention,- Figure 1 is a view in side elevation of a multi-cylinder engine, and Fig. 2 is a vertical cross-section thereof on a somewhat larger scale.

. 3 indicates the base of the engine which rests on any suitable foundation. Mounted 1 device by the pipe 14, and

' air between the on top of it is a secondary base portion 4 that is provided with openings to receive the which as many vertical water jacketed cylinders 5 of may be provided as are de-- sired. The cylinders are open at both ends, the lower end being larger in diameter than the upper to form the cylinder 6 of the scavenging air pump; In other words the cylinders'are of the differential type. In the working cylinder 7 are two oppositely moving pistons 8' and 9 which in addition to driving themain shaft control the, exhaust ports 10 and the scavenging air ports 11. Between the ends of the pistons when they strokes is a combustion chamber 12 of proper size to secure the line with this chamber are one or more devices 13 for injecting oil under air pressure into the body of highly heated compressed pistons. Air compressed to a higher pressure than that due to compresson by the pistons .is admitted tothe said oil is admitted To accommodate the .placed 180 and are are at the inner portions of theirdesired compression. In.

cylinder takes place at thereto from a high pressure pump (not shown) by the pipe 15.

The exhaust ports are angularly displaced around the cylinder and discharge into an annular chamber 16 that in turn discharges into the exhaust pipe 17. The exhaust pipes for the several cylinders open into the manifold 18 which may communicate with a mufller of any suitable construction. The scavenging -air ports are also displaced around the cylinders and communicate with the annular chamber 19 the later communicating with the receiver 20 which is common to all of the pumps.

The outer piston 9 is provided with a fork 21 through which extends the cross head 22, the two being united by the pin 23. ve tical movements of the cross-head the cylinder is slotted at 24:. To. the ends of the cross-head are attached side rods 25 which in turn are united at their lower ends to cross-heads 26, the latter being connected by rods 27 to cranks on the main shaft 28. The inner working piston 8 and the air pump piston 29 united therewith are connected to a crank on the main shaft by the rod 30. The crank pins for the upper and lower pistons are disequally distant from the axis of the shaft.

Air is admitted to the pump cylinder through one or more suction. valves 31 on the downward stroke of the piston. The valves may be provided with light springs to insure their prompt seating on the upward or compression stroke of the piston. Air is discharged from each p'ump cylinder through a pipe containing a check valve 32 into a manifold 33 which communicates with the receiver 20.

The pistons in the second cylinder and the cranks therefor are so related with respect to those of the first, that when the first cylinder has been exhausted the air in. the second cylinder has been compressed to the maximum. The discharge of fuel into each or about the dead center position of the cranks.- Usually it will be found most satisfactory to have the fuel valve open a few degrees in advance of the .dead center position of the cranks to insure the combustion starting at the proper time v In order to protect the external moving parts of the engine, each cylinder is provided with a suitably formed casing 34 that is supported in any suitable manner, as by the base 4 for example.

It is evident thatthe outer piston 9 and said masses and to the arrangement of the cranks and connecting rods. To compensate for this weight has to be added to the inner piston. Now instead of adding dead weight at this point, I add the air pump piston 29 and so design it that its weight plus that of the inner piston 8 and connecting rod 80 will balance or substantially balance the weight of the outer piston 9 and its associated parts. This pump should have a capacity equal to the displacement of both working pistons plus about thirty-five per cent: In addition to avoiding the unbalanced effects my improved arrangement avoids the use of a separate air pump for scavenging purposes there;

by resulting in a saving in the cost of con struction and a decrease in the number of parts required. This arrangement also results in a saving in space'which is an important factor in all power installations and and in particular -when the engine is intended, as in the present case, to be installed on a motor car for driving an electric generator which supplied current to 'motors mounted on a truck.

The operation of my improved engine is as follows: Assuming that the upper piston has uncovered the exhaust ports 10, this being the end of the firing stroke, the burned gases will pass outward from the cylinder to the pipe 17 At about this time the lower piston 8 uncovers the scavenging air ports 11 and air from the receiver will be discharged into the cylinder and thoroughly clean it. The downward movement of the piston 29 has sucked into the cylinder 6 a change of pure air, the discharge valve 32 being closed. This means that the air for scavenging the first working cylinder is received from the scavenging pump operating in conjunction with the second working cylinder. The transfer of air between the pumps and the cylinders takes place through the receiver 20 which purposely has a relatively large capacity to facilitate scavenging. The amount of air however used in scavenging one working cylinder must be replaced or delivered to the receiver by the pump cooperating with the other working cylinder. After the scavenging operation the ports 10-and 11 are closed by the pistons and further movement thereof compresses the air in the working cylinder to a relatively high degree, the temperature of said air being above that required to ignite the fuel discharged by the devices 13. The firing of the mixture causes the pistons to move away from each other until the exhaust ports 10 and scavenging ports 11 are successively opened. The cycle of operation is then continued, it being the same in all of the cylinders.

For the sake of simplicity I have not shown the injection devices in detail nor tne cam o'r; cams driven by the main shaft for controlling the operation of the fuel admitting valve or valves. For the same reason the oil pump and the source of compressed air for pipe 14 have been omitted.

In using the term inner piston I refer .to the one nearer the crank shaft, and in ,using the term outer piston to the one remote therefrom.

The arrangement herein described is best adapted for engines having two cylinders or multiples thereof because of the ease with which the scavenging air can be handled.

In accordance with the provisions of the patent statutes, I have described the principle of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof; but I desire to have it understood that the apparatus shown is only illustrative, and that the invention can be carried out by other means. VVhat I claim as new and desire to secure by Letters Patent of the United States, is: 1. In a two-cycle engine, the combination of a differential cylinder, oppositely moving working pistons mounted therein which compress the charge of air between them to a point where its temperature is above the fuel igniting temperature, exhaust and scavenging ports in the cylinder which are controlled by the pistons, an air pump piston that is located in the portion of the cylinder having the larger area, a crank shaft, power transmitting means between the pistons" and the crank shaft, the weight of the outer piston and its power transmitting means being substantially balanced by that of the inner working piston, its power transmitting means and the air pump piston, a device for discharging fuel ,into the body of compressed air between the working pistons, and means for conveyand'moving with the adjacent working pis- I cylinder,

'an' air pump piston located in the enlarged ton, a crank shaf power transmitting means between the working pistons of each cylinder and said crank shaft, the power trans mitting means for each cylinder being so related to that of the other that when the first cylinder has been exhausted the air in the second cylinder has been compressed, means for transmitting air delivered by the pump in one cylinder to. the scavenging ports of another cylinder, and means" for introducing-fuel into the cylinders.

3. In a two-cycle engine, the combination of open ended differential cylinders, a pair of oppositely moving pistons in each admission and scavenging ports,

portion of each cylinder and which is connected to its inner working piston, a crank shaft, power transmitting means between the inner and outer working pistons and the crank shaft, the weight of each outer piston and its power transmitting means being substantially balanced by that of the inner piston, its power transmitting means and connected air pump piston, means for transmitting air delivered by one pump to the scavenging .ports of an adjacent working cylinder, and means for introducing fuel int-o the cylinders.

In witness whereof, I have hereunto set my hand this-19th day of April, 1912.

HENRI e. CHATAIN.

/ Witnesses: Y 7

S. J. SMITNEY, I ALEX F. MACDONALD. 

